import java.io.*;
import java.util.*;
import java.math.*;

public class Solution {

    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        BigInteger a = s.nextBigInteger();
        BigInteger b = s.nextBigInteger();
        BigInteger t = s.nextBigInteger();
        BigInteger result = a.add(b).divide(BigInteger.valueOf(2)).modPow(t, BigInteger.TEN.pow(9).add(BigInteger.valueOf(7L)));
        System.out.println(result);    
    }
}